通过点击并拖动它来移动屏幕上的元素的能力。 这在SVG中可以比较容易实现，如下所示。
实现代码如下所示 -
<html xml:lang="en" lang="en"
xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<script type="text/javascript" src="snap.svg-min.js"></script>
<script type="text/javascript">
var startX = 100;
var startY = 100;
function init() {
Snap("#button").click(resetFcn);
Snap("#buttonText").click(resetFcn);
Snap("#circle").drag(dragMove, dragStart, dragEnd);
}
function resetFcn(evt) {
Snap("#circle").attr({cx: 100, cy: 100});
}
function dragStart(x, y, evt) {
// figure out where the circle currently is
startX = parseInt(Snap("#circle").attr("cx"), 10);
startY = parseInt(Snap("#circle").attr("cy"), 10);
}
function dragMove(dx, dy, x, y, evt) {
Snap("#circle").attr({cx: (startX + dx), cy: (startY + dy)});
}
function dragEnd(evt) {
// no action required
}
</script>
</head>
<body onload="init()">
<div style="text-align:center">
<svg width="600" height="400" viewBox="0 0 200 200"
xmlns="http://www.w3.org/2000/svg"
xmlns:xlink="http://www.w3.org/1999/xlink">
<circle id="circle" cx="100" cy="100" r="30"
style="fill:#663399; stroke: black"/>
<rect id="button" x="74" y="170"
rx="5" ry="5" width="50" height="25"
style="stroke:black; fill:#ddd; cursor:pointer"/>
<text id="buttonText" x="100" y="187" class="buttonText"
style="fill:black; stroke:none;
font-family: sans-serif; font-size: 12pt;
text-anchor:middle; cursor:pointer">Reset</text>
</svg>
</div>
</body>
</html>
代码下载:https://www.yiibai.com/downloads/svg/drag.zip
